Table 2 Multivariable Cox proportional hazards model for time to initiation of minocycline or doxycycline

Male sex

1.139

0.887, 1.464

0.146

0.308

Age

0.990

0.982, 0.998

0.004

0.021

Number of previous nonbiologic DMARDs

1.618

1.532, 1.710

0.045

< 0.001

Methotrexate use

0.728

0.596, 0.890

0.074

0.002

Leflunomide use

0.622

0.470, 0.822

0.089

0.001

Azathioprine use

0.378

0.186, 0.769

0.137

0.007

Patient Activity Score

1.049

1.000, 1.100

0.026

0.051

Comorbidity index

1.139

1.072, 1.210

0.035

< 0.001

Number of previous biologic DMARDs

0.779

0.676, 0.898

0.057

0.001

Calendar year

1.062

1.001, 1.127

0.032

0.046